Front Wiper Inop Aggrivation

[djelectron]

I have the weirdest set of concurrent issues. The last few times I've driven the truck I've had the front wipers (I have intermittent) randomly want to work or not. Whenever they aren't working, the tailgate window, rear wiper, and rear defrost stop working as well. Sometimes in the same drive, the wipers start working again, and magically, I can raise the rear window and do everything else. I can always raise the window with the key from outside, and the rear wiper and defrost work perfectly - as long as the fronts are working. When I hit the front wiper or washer and it works, I hear a relay click fairly quietly. A few seconds later when they stop working, no more click.

Now, the front wipers are completely dead.

I've been through the repair and electrical service manuals and scoured the internet until my eyes are bloodshot. The only thing that I can find similar is a post here from 2005: http://www.toyota-4runner.org/classic-t4rs/14909-94-w-3vze-wipers-dont-work.html"]94 w/3VZE wipers don't work The OP on that 12 year old post never got back with results, so I though it best to start a new thread.

I checked every fuse under the hood and kick panel. I pulled the steering wheel, pulled the multi function switch, and tested for continuity on all the pins the manual suggests. All good. I also checked the harness on the column for 12v power and was good. As I understand it, there is a relay in the back for everything rear-related, but that doesn't explain why the front wipers aren't working. I don't see any electrical connection between the two systems except the switch.

Thanks for your ideas and help!

 

[djelectron]

Today I took the wiper switch apart again. I was suspecting the relay. I removed it from the pcb and took it apart. When applying power to the coil, the relay clicks from one lead to the other. I don't know exactly what type of relay it is called. There is a power coil circuit that moves the contact, there is a line in, and two lines out. Applying power to the coil just switches the output from one out to the other. Anyways that works just fine, so I reinstalled it. I tested the continuity again per the manual and found the switch working perfectly. I also tested the harness under the column and found power where it was supposed to be.

I then tested the motor itself, jumping 12v to the fast motor lead and then to the slow motor lead. Both of them worked fine, of course. When I put everything back in though, no wipers.

One thing I did notice is that the rear defroster does work. The rear window still does not, but the defroster does.

I'm still just as stumped as ever, and I'm hoping someone might have some ideas.

Thanks again!

 

[RAD4Runner]

... I also checked the harness on the column for 12v power and was good....

Got schematic? I have a first-gen but can help IF i saw the schematic.
Did you trace the wiring and relays from that point to the wiper motor? Did you find out where you stopped having 12V?

 

[djelectron]

Got schematic? I have a first-gen but can help IF i saw the schematic.
Did you trace the wiring and relays from that point to the wiper motor? Did you find out where you stopped having 12V?

Thanks rad. I have the schematic. I'll pm you a link.

No. I didn't find the point yet where I lose power. Just ran out of time yesterday. All I know at this point is I have 12v at the harness on the column.

 

[djelectron]

I finally figured out the issue!

I had a multimeter in the spot for the wiper fuse checking to make sure I had 12v on the hot side, and I did. I put the multimeter on the output side of the fuse block to test for continuity to the hot pin on the column wire harness, and I did. I plugged the fuse back in, and I still had nothing. Everything was right everywhere, but nothing was working.

It's when I pulled the fuse out and reinserted it a couple of times I found the problem. It was loose. The output side connector was not making good contact. I put the fuse back in, pulled it to one side, turned on the ignition, hit the wipers, and finally they worked! Now I just have to fix the pins in the fuse box so they make good contact again. It'll be good to finally be back on the road!

 

[djelectron]

Put some solder on the fuse, and we're good to go! I can see out of the windshield finally, and the wipers seem a little faster than they ever have.

 

[RAD4Runner]

I finally figured out the issue!
...!

Glad you found the issue.
Often times it's poor connection/wiring, poor assembly or poor maintenance that causes problems on our Yota's.

 

[djelectron]

Glad you found the issue.
Often times it's poor connection/wiring, poor assembly or poor maintenance that causes problems on our Yota's.

And thank you for your help! Don't forget the other problems our trucks face. They're the same ones you and I deal with a little more each day... AGE. lol

One of these days, I'll just have to go through and refresh the fuse box altogether. For now, I'm going to go out and have some fun!